This study aims to fully utilize the unique germplasm resources of ancient tea plants in Guizhou, China. Using cutting seedlings derived from the easily propagated and rooted ancient tea tree single-plant variety TZRR1 (Camellia sinensis L. cv. Tongzi rapid rooting1, TZRR1), which was obtained through preliminary screening, as the research material. Phenotypic observations revealed that TZRR1 has abundant trichomes on the buds, yellowish-green leaves, and a high oil sheen. The weight of hundred buds with two leaves was 33.45 g. Compared with Fudingdabaicha (Camellia sinensis cv. Fudingdabaicha, FDDB), TZRR1 had a higher water content in the buds and leaves. Paraffin section analysis revealed that the xylem area in the leaves and stems of the TZRR1 variety was reduced compared with FDDB. Further analysis of lignin relative content showed that TZRR1 was significantly(p<0.05) lower than that in FDDB. Biochemical measurements of tea indicated that the content of tea polyphenols and water extract contents in the steamed samples of TZRR1 with one bud and two leaves were significantly higher than that of FDDB, with a phenol-ammonia ratio of 6.74. Using GC-MS (gas chromatography-mass spectrometry) technology revealed differences in the aroma components and their relative contents in the fresh leaves and steamed green samples of TZRR1 and FDDB. The fresh leaves of TZRR1 contained higher relative contents of limonene, methyl salicylate, (E)-linalool oxide, and furfural acetate, while the fresh leaves of FDDB contained higher relative contents of benzaldehyde, benzothiazole, linalool, and geraniol. The steamed green samples of TZRR1 primarily exhibited floral and fruity aromas, with benzyl alcohol, nonanal, jasmine ketone, cis-3-hexenyl caproate, and ionone being the main aroma-contributing substances. The steamed green samples of FDDB mainly presented woody and floral aromas, with cedrol, carotene seed oil, nerolidol, α-farnesene, cedrene, and caryophyllene being the main aroma-contributing substances. This study lays a theoretical foundation for the further development and utilization of ancient tea tree single-plant TZRR1.

To screen host RNA-binding proteins interacting with the infectious bronchitis virus (IBV) N protein, providing a basis for elucidating the virus-host interaction mechanism, co-immunoprecipitation (Co-IP) combined with mass spectrometry was employed to identify host proteins interacting with the N protein with the monoclonal antibody 4H4 against IBV N protein. Differentially expressed proteins were subjected to bioinformatics analysis, and Co-IP experiments were conducted to validate the interactions between the N protein and candidate RNA-binding proteins. The results showed that a total of 847 differentially expressed proteins were identified, primarily involved in processes such as transcription, translation and protein modification, protein-RNA complex assembly, signal transduction, and energy metabolism. Co-IP experimental results indicated that interactions exist between the N protein and the host RNA-binding proteins TARDBP, hnRNPK, FUBP3, and hnRNPA1. This study identified host proteins interacting with the IBV N protein, which are involved in multiple key stages of the viral replication cycle. The interactions between the N protein and RNA-binding proteins provide new research directions for elucidating the specific mechanisms of host proteins in viral infection.

To address the issues including CO₂ deficiency induced by poor ventilation in solar greenhouses during autumn and winter in northwest China, the tomato cultivar Jintao 19 was used as the test material. Five treatments were established in the solar greenhouse: CK1 (bare soil without mulching), CK2 (plastic film mulching on ridges), T1 (plastic film mulching on ridges + straw mulching in furrows), T2 (straw mulching on ridges), and T3 (full straw mulching). The growth and development of tomato plants, as well as the CO₂ concentration and distribution in the greenhouse, were determined to screen the optimal ground mulching regime. The results showed that compared with CK1, the CO₂ concentrations at the near-ground layer, canopy layer, and upper canopy layer under T1 were significantly (p<0.05) increased at 13:00, 21:00, 01:00 and 05:00. The contents of chlorophyll a and chlorophyll b were significantly elevated, the plant height, stem thickness and leaf number were significantly enhanced, and the contents of nitrogen (N), phosphorus (P), and potassium (K) in stem and leaf, as well as P and K contents in root, were also significantly increased under T1 treatment than those under the CK1 treatment. The net photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, root activity and root volume were significantly increased by 53.12%, 10.34%, 53.64%, 5.10%, 70.34%, respectively, under T1 treatment than those under the CK1 treatment. In conclusion, plastic film mulching on ridges combined with straw mulching in furrows can promote tomato growth and dry matter accumulation by elevating CO₂ concentration in the greenhouse and enhancing plant photosynthesis.

To investigate the effects of photoperiod on the growth and quality of pakchoi (Brassica campestris ssp.chinensis Makino) in plant factories with artificial lighting, four varieties of pakchoi were selected as experimental materials. Four photoperiod treatments were applied: T1, 10 h light/14 h dark (10 L∶14 D); T2, 13 h light/11 h dark (13 L∶11 D); T3, 16 h light/8 h dark (16 L∶8 D); T4, 19 h light/5 h dark (19 L∶5 D). Biomass, growth indices, quality indices, and photosynthetic parameters were measured. The results showed that moderately extending the photoperiod (16 L∶8 D) could improve photosynthetic efficiency and increase plant biomass. The variety Ziyi exhibited the highest shoot fresh weight under the 19 L∶5 D treatment, which was 15.48% higher than that under 13 L∶11 D treatment. The varieties SH-2, Xinxiaqing No. 9, and Yanqing achieved the highest shoot fresh weight under the 16 L∶8 D treatment, with increases of 16.00%, 16.96%, and 23.68%, respectively, compared with 13 L∶11 D treatment. Moderately extended photoperiods also increased the contents of soluble sugars, soluble proteins, and anthocyanins while reducing nitrate content. However, excessively prolonged photoperiods (light duration 19 h·d^-1) led to yield decline and reduced appearance quality during later growth stages, thereby diminishing marketability. This might be attributed to reduced overall PSII activity in some pakchoi varieties under such conditions, consequently inducing photoinhibition. It is recommended to appropriately increase the light duration (16-19 h·d^-1) during the seedling stage and reduce it to approximately 16 h·d^-1 in later growth stages to ensure both yield and quality in pakchoi production within artificial light plant factory.

Exogenous sodium acetate (NaAc) can promote indole-3-acetic acid (IAA) synthesis during the primordium stage of Volvariella volvacea, thereby promoting primordium differentiation and increasing yield, but its specific mechanism of action has not been elucidated. This study aimed to analyze the ability of NaAc to induce IAA synthesis. Using a submerged culture method, a three-factor experiment was designed with five pH value gradients(6, 7, 8, 9, 10), four anions (Ac^-, HCO₃^-, C₅H₇O₅COO^-, H₂PO₄^-), and four cations (Na⁺, Mg²⁺, Mn²⁺, K⁺) to investigate the effects of adding NaAc on mycelial biomass and IAA synthesis, providing a theoretical basis for subsequently revealing the mechanism by which NaAc regulates IAA synthesis. The results showed that under pH value 8 conditions, mycelial biomass, aldehyde dehydrogenase (ALDH) activity, and the contents of IAA, indole-3-acetaldehyde (IAAld), indole-3-pyruvic acid (IPyA), tryptamine (TAM) and indole-3-acetaldoxime (IAOx) were significantly (p<0.05) increased by 37.98%, 58.39%, 61.29%, 58.33%, 31.25%, 29.23% and 64.71%, respectively. Among the anions, acetate ions (Ac^-) significantly increased biomass, IAA content, and ALDH activity by 6.28%, 22.58%, and 21.01%, respectively, the contents of IPyA, TAM, and IAOx were also significantly higher than the control. Among the cations, Na⁺ significantly increased biomass, IAA content, and ALDH activity by 6.28%, 22.58% and 20.97%, respectively, and the contents of IPyA, TAM, and IAOx were also significantly higher than the control. This indicated that Na⁺ was superior to Mg²⁺, Mn²⁺, and K⁺ in promoting IAA synthesis. Comprehensive analysis showed that during the vegetative growth stage of V. volvacea, adding NaAc could maintain the culture environment pH value within an alkaline range suitable for growth. pH value, as the main regulatory factor after NaAc dissociation, together with Ac^- and Na⁺, influenced biomass accumulation and IAA synthesis during the growth stage of V. volvacea.

Vegetative branches promote rose growth by increasing the photosynthetic area, allowing more nutrients to accumulate and transport to commercial flower branches. To investigate the effects of the number of vegetative branches on the canopy and biomass of roses, a randomized complete block design was adopted to quantify the relationship between the number of vegetative branches and the accumulation of biomass in commercial flower branches. The plant height, dry weight, photosynthetically active radiation (PAR) of commercial flower branches and vegetative branches of cut roses were measured under 1-3 vegetative branches treatments. The results showed that the plant height of commercial flower branches treated with three vegetative branches significantly (p<0.05) increased by 87.83% and 45.79% compared with those treated with one or two vegetative branches. The total dry weight of commercial flower branches treated with three vegetative branches significantly increased by 134.69% and 52.40% compared with those treated with one or two vegetative branches. Under the treatment of three vegetative branches, the average PAR utilization rate of vegetative branches was the highest, at 30.46 g·MJ^-1, which was 84.16% higher than the treatment of two vegetative branches and 219.29% higher than the treatment of one vegetative branch. According to the grading evaluation of fresh cut roses, the total number of commercial flower branches under the treatment of three vegetative branches was 54, of which 4 were A-grade, accounting for 57.14% of the total number of A-grade commercial flower branches. There were 10 B-grade branches, accounting for 52.63% of the total number of B-grade commercial flower branches. Under the treatment of three vegetative branches, the commercial flower branches had the highest plant height, total dry weight, PAR utilization rate, and cut flower grade, indicating that vegetative branches have a positive effect on the growth and biomass accumulation of commercial flower branches.

To elucidate the genetic relationship and evolutionary variations among different flower colors of bluebell (Hyacinthoides non-scripta), a cytological analysis was conducted to provide reliable evidence for polyploid breeding strategies. Karyotype analysis and fluorescence in situ hybridization (FISH) using 45S rDNA, 5S rDNA, and telomere repeats as probes were performed on white-flowered and blue-flowered bluebells. Karyotype analysis revealed that the white bluebell was diploid, with a chromosome number of 2n=2x=16, with an average arm ratio of 4.07, a karyotype asymmetry coefficient of 75.18%, and a karyotype formula of 2n=2x=16=2m+6sm+4st+4t(sat). The blue bluebell was triploid, with a chromosome number 2n=3x=24, with an average arm ratio of 4.27, a karyotype asymmetry coefficient of 75.20%, and a karyotype formula of 2n=3x=24=3m+9sm+6st+6t(sat). Both varieties exhibited a 3B karyotype, with satellite DNA located at the ends of the short arms of two pairs of telocentric (t) chromosomes. The 45S rDNA signals were localized on the chromosomal secondary constrictions and 5S rDNA signals were localized on the top of the long arm of the metacentric (m) chromosome by FISH results. Telomeric repeat sequences were uniformly distributed at both ends of each chromosome, without interstitial signals. White bluebells displayed four 45S rDNA and two 5S rDNA signal sites, while blue bluebells exhibited six 45S rDNA and three 5S rDNA signal sites. Karyotype analysis and FISH signal localization indicated that blue bluebells likely originated from whole-genome duplication of the white bluebell, providing a cytological theoretical basis for polyploid breeding in bluebells.

To identify the pathogen causing leaf spot disease on Hydrangea macrophylla Bo Dalan and investigate its biological characteristics and effective control agents, thereby providing a theoretical basis for the scientific management of this disease, this study isolated the pathogen from diseased samples collected at the Nanguo Shanhua Hydrangea Germplasm Resource Base in Yuxi City, Yunnan Province, using the tissue isolation method. The pathogenicity was verified according to Koch’s postulates. The pathogen was identified based on morphological observations and multi-gene sequence (ITS, LSU, TUB) analysis. The effects of different culture media, carbon sources, nitrogen sources, temperature, light conditions, and pH value on the mycelial growth of the pathogen were studied using the mycelial growth rate method. Additionally, nine commonly used fungicides were selected to determine their in vitro toxicity against the pathogen. The results showed that the primary pathogen isolated from the infected leaves was Epicoccum sorghinum. The biological characteristics tests indicated that the optimal conditions for mycelial growth were PDA medium with maltose as the carbon source and peptone and beef extract as nitrogen sources, at a temperature of 25 ℃, pH value 7.0, and under continuous light. The in vitro toxicity tests revealed that 10% difenoconazole water dispersible granules (WG) had the best inhibitory effect, with an EC₅₀ value of 1.252 2 mg·L^-1. In conclusion, the pathogen causing leaf spot disease on H. macrophylla Bo Dalan was E. sorghinum, and 10% difenoconazole WG exhibited a strong inhibitory effect against this pathogen, making it a potential candidate for field control.

Brown spot disease caused by Alternaria spp. is an important disease on flue-cured tobacco, but there are few studies on the pathogen species causing brown spot on cigar tobacco. This study aimed to clarify the pathogen species causing brown spot on cigar tobacco in Sanming region of Fujian Province and their pathogenicity to cigar tobacco varieties. Brown spot samples were collected from the cigar tobacco Haiyan 101 grown in the Sanming region. Pathogens were isolated and purified on PDA medium. Identification was performed by combining morphological and molecular biological methods [multigene (ITS, TEF1, RPB2, GAPDH, Alta1) phylogenetic analysis and His3 single-gene supplementary analysis]. The results showed that the 45 isolates belonged to four species: 9 were Alternaria alternata, 21 were Alternaria tenuissima, 12 were Alternaria longipes, and 3 were Alternaria gaisen. Pot inoculation pathogenicity tests showed that 3 d after inoculating Haiyan 101, all four Alternaria species could produce circular brown lesions on leaves. Among them, A. longipes exhibited the strongest pathogenicity, while A. gaisen showed the weakest pathogenicity. This is the first report of A. gaisen causing tobacco brown spot disease. Field inoculation tests showed that A. tenuissima and A. longipes were highly pathogenic to all five cigar tobacco varieties (Haiyan 101, QX107, QX105, CX80 and QX103). A. alternata showed weak pathogenicity to varieties QX107 and QX105 but strong pathogenicity to the other three varieties. A. gaisen showed weak pathogenicity to all five varieties. The findings of this study provided guidance for the control of brown spot disease on cigar tobacco and the breeding of resistant varieties.

To investigate the effects of long-term application of different organic materials on the stability of soil aggregates and the contents of organic carbon and total nitrogen in soil aggregates of yellow clayey paddy soil, a field plot experiment was carried out in a rice paddy field in Jinhua City, Zhejiang Province of China from 2011 to 2023. Three treatments were designed in the experiment, namely chemical fertilizer alone (NPK), combined application of chemical fertilizer and straw with rapid decomposer (RS), and combined application of controlled-release bulk-blended (BB) fertilizer and decomposed cow manure (CM). Topsoil (0-20 cm) samples were collected after the late rice harvest in 2023. Soil aggregates with different particle sizes were separated by the wet sieving method. The proportion (mass fraction), organic carbon content and total nitrogen content of aggregates in each particle size fraction were determined. The mean weight diameter (MWD), geometric mean diameter (GMD) and the proportion (mass fraction) of soil aggregates>0.25 mm (R_0.25) were calculated, and the storages of organic carbon and total nitrogen in aggregates of each particle size fraction were estimated. The results showed that compared with the NPK treatment: the RS treatment significantly (p<0.05) reduced the proportion of aggregates with particle size ≤0.25 mm in the soil; the CM treatment significantly decreased soil bulk density and the proportion of aggregates with particle size ≤0.25 mm, and significantly increased the proportion of aggregates with particle sizes of >2.00 mm and >0.25-1.00 mm, as well as the values of MWD, GMD and R_0.25. Compared with the NPK treatment, the CM treatment significantly increased the organic carbon storage and its contribution rate of aggregates with particle sizes of >2.00 mm by 66.91% and 11.23 percentage points, respectively, and significantly increased the total nitrogen storage of aggregates with particle sizes of >2.00 mm by 43.89%. Correlation analysis indicated that the stability of soil aggregates was mainly affected by aggregates with particle sizes of >2.00 mm and >0.25-1.00 mm. Overall, both the CM and RS treatments contributed to improving the stability of soil aggregates and the storages of organic carbon and total nitrogen in soil aggregates, and the effect of the CM treatment was superior to that of the RS treatment. Therefore, the combined application of controlled-release BB fertilizer and decomposed cow manure can be adopted as an effective measure to enhance the stability of soil aggregates and regulate the soil organic carbon pool and nitrogen pool in yellow clayey paddy soils in central Zhejiang.

Soil acidification and low nitrogen use efficiency are key constraints to sustainable agriculture in southern China. A 5-year long-term field experiment with a Chinese cabbage-sweet potato rotation was conducted to systematically explore the effects of combined biochar and biogas slurry application on nitrogen transformation in acidic red soil. Five treatments were set: no fertilizer control (CK), chemical fertilizer alone (C0B0), biogas slurry substituting chemical fertilizer (C0B1), biochar combined with chemical fertilizer (C1B0), and biochar combined with biogas slurry (C1B1). Results showed that combined biochar and biogas slurry application significantly (p<0.05) ameliorated soil acidity. Soil pH value in C1B1 increased from an initial value of 5.44 to 7.13 after 5 years, which was significantly higher than that in C0B0 by 2.05. Compared with CK, urease activity in C1B1 significantly increased by 30.0%, while nitrate reductase and nitrite reductase activities decreased significantly by 35.2% and 36.3%, indicating a shift in the nitrogen cycle from nitrification-denitrification dominance to nitrogen fixation-assimilation dominance. Microbial community analysis showed that C1B1 significantly increased the relative abundance of nitrogen-fixing bacteria but decreased the relative abundance of nitrifying bacteria compared with C0B0. The 5-year average yields of Chinese cabbage and sweet potato in C1B1 were 56.31, 46.17 t·hm^-2, respectively, and the agronomic efficiency of nitrogen (AEN) was 234.4, 220.4 kg·kg^-1, respectively, in the Chinese cabbage season and sweet potato season, which were all significantly higher than those of C0B0. Structural equation modeling identified pH as the core driver regulating the nitrogen cycle, and random forest modeling showed that the pH value of 6.5 was the critical threshold for a sharp increase in AEN. In conclusion, combined biochar and biogas slurry application optimizes nitrogen transformation in acidic red soil through pH-mediated multi-level regulation, which can reduce chemical fertilizer input while ensuring yield, providing a scientific basis for reducing chemical fertilizer application and improving efficiency.

To investigate whether pesticide residues would limit the amount of manure returned to fields and the quantity of livestock and poultry farming, this study took paddy fields in Zhejiang Province as the research object in crop planting, broiler and laying hens farming as the research objects in animal husbandry, and imidacloprid as the pesticide type for study. According to the flow characteristics of imidacloprid between crop planting and animal husbandry, this study constructed a paddy field carrying capacity model of chicken manure based on the ecological risk value of imidacloprid by using material flow analysis, risk quotient method and soil environmental impact prediction. Considering the variability of parameters such as soil physicochemical parameters, pesticide residues in soil and chicken manure, and chicken manure excretion, the Monte Carlo analysis method was used to estimate the appropriate variation range of broiler or laying hens farming scale. Our results showed that the short-term, medium-term and long-term carrying capacity of broiler breeding per hectare in Zhejiang Province were 38 064-62 793, 5 336-15 759 and 0-1 492 birds, respectively, and those of laying hens breeding were 4 996-9 188, 715-2 245 and 0-205 birds, respectively. If imidacloprid residues in broiler manure and soil decreases by 25%, the carrying capacity of broiler farming per hectare will increase by 33.3% and 8.4%, respectively. Considering the development needs of livestock and poultry farming and the protection of farmland soil environment, it is recommended to actively promote pesticide reduction and efficiency enhancement technologies to reduce imidacloprid residues in soil. Meanwhile, pesticide residues in manure should be monitored to promote the green development of crop planting and animal husbandry in Zhejiang Province.

To explore the nutritional and quality differences of Lanmei 1 blueberry fruits from four production areas, Zhejiang, Sichuan, Jiangxi, and Anhui, this study compared the metabolite profiles of fruits from different origins through metabolomic analysis and nutritional indicator determination, and selected blueberries from Sichuan for processing suitability investigation. A total of 2 167 metabolites were identified. Compared with other origins, Zhejiang blueberries exhibited a larger number of significantly differential metabolites, rich in unique components such as organic acids, esters, flavonoids, and their derivatives; Sichuan and Anhui blueberries showed relatively abundant differential metabolites, containing more flavonoids and organic oxygen compounds; Jiangxi blueberries had the highest content of organic oxygen compounds but lower uniqueness in flavonoids and anthocyanins. Metabolic pathway analysis indicated that, compared with Zhejiang, metabolites in Sichuan and Jiangxi blueberries were enriched in amino acid and linoleic acid metabolism pathways, while Anhui blueberries were enriched in flavonoid biosynthesis pathways. Due to higher vitamin C and soluble sugar content, Sichuan blueberries were more suitable for processing than for fresh consumption. Evaluation of their basic processed products showed that preserved fruits retained nutrients relatively well, while juice processing requires optimization. Blueberries from Sichuan were more suitable for deep processing, such as functional foods, to fully utilize their nutritional advantages. The metabolomic data obtained in this study could provide a scientific basis for blueberry raw material selection and processing applications.

To clarify the quality and safety status of coastal mudflat mariculture in Zhejiang Province of China, a sensitive analytical method was established for the simultaneous determination of 16 pesticide residues (including organophosphorus, pyrethroid, and macrolide pesticides) in aquatic products and their mariculture environment using dispersive solid-phase extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry. Samples were extracted with 2% acetic acid in acetonitrile, and the extracts were purified using QuEChERS extraction salt packets and QuEChERS cleanup tubes prior to instrumental analysis. This method was applied to determine the residual levels of the 16 target pesticides in mudflat shellfish and their mariculture environment from typical mariculture areas in southern Zhejiang during 2024-2025, and a dietary exposure risk assessment was conducted for the detected pesticides. It was shown that the established method exhibited good linearity for all 16 pesticides in the concentration range of 1-50 ng·mL^-1, with coefficients of determination (R²) all exceeding 0.995. The recoveries at four spiked levels (4, 10, 20, and 50 μg·kg^-1) ranged from 65.21% to 120.00%, with relative standard deviations (RSDs) of 0.24%-11.17%. The limit of quantification (LOQ) of triazophos was 0.1 μg·kg^-1 in biological samples, 0.5 μg·kg^-1 in sediment samples, and 0.5 μg·L^-1 in water samples; for the other 15 target pesticides, the LOQs were 0.2-4.0 μg·kg^-1 in biological samples, 0.8-10.0 μg·kg^-1 in sediment samples, and 0.8-10.0 μg·L^-1 in water samples. By using the established method, triazophos and fenpropathrin residues were detected in shellfish samples, and triazophos residue was detected in sediment samples, while no pesticide residues were found in water samples. The chronic dietary risk of the two detected pesticides ranged from 0.007% to 0.578%, and the acute dietary risk ranged from 0.845% to 51.798%, all below 100%, indicating that the dietary exposure risks were within an acceptable range.

To study the residue elimination pattern of enrofloxacin and its metabolites (ciprofloxacin) in Jiangshan black-bone chickens, 76 Jiangshan black-bone chickens, of similar size, half roosters and half hens, were raised under the same feeding conditions until 97-107 days of age. Enrofloxacin soluble powder was administered continuously at a dose of 0.75 g per liter of drinking water for 5 d. Samples of muscle, liver, kidney and sebum were collected at 5, 7, 10, 14, 21, 28 and 42 d after drug withdrawal. The residues of enrofloxacin and its metabolites were detected using liquid chromatography-tandem mass spectrometry. The withdrawal periods for enrofloxacin and its metabolite in roosters and hens were calculated using WT1.4 software. The results showed that the withdrawal periods in hens were 148.2, 17.6, 57.4 and 232.3 d for muscle, liver, kidney and sebum, respectively; in roosters, the withdrawal periods were 115.2, 19.1, 60.7 and 259.9 d, respectively. To ensure that enrofloxacin residues in Jiangshan black-bone chicken meet the regulatory requirements, it is recommended that the withdrawal period be set at no less than 260 d.

A scraper-type film stripping device was developed to tackle the problems of film leakage and unsatisfactory stripping performance in the operation of spring-tooth residual film recovery machines. The device is structurally composed of a scraper, a rotating shaft and other auxiliary mechanisms. By integrating the structural parameters of the machine frame and the operating principle of the film stripping device, its key structural parameters were determined via theoretical analysis and calculation, and the optimal operating rotational speed was obtained as 187 r·min^-1. Modal analysis and transient dynamic analysis were performed on the device using ANSYS software. The first order to the sixth order mode shapes were acquired through modal analysis, and the results demonstrate that the minimum natural frequency of the film stripping plate is 6.22 Hz, which exceeds the frequency generated by external periodic loads, thereby avoiding resonance failure. The transient dynamic analysis results show that the total deformation of the film stripping plate is 3.32×10^-2 m, and its maximum equivalent stress is 1.204 7×10^-1 MPa. Field experiments were implemented to test the operational performance of the film stripping device. The measured film stripping rate reached 87.88% and the film entanglement rate was 1.73%, which satisfy the operational specifications of agricultural film-stripping equipment. The proposed design features a simple structure and high reliability, which can reduce film leakage during stripping operations, and improve the stripping performance and operating efficiency of the device.

Aiming at the problems of damage to tree branches and complex mechanical operation in vibration harvesting machine for Camellia oleifera fruit (camellia fruit), a remote-controlled layered harvester for camellia fruit is designed in this paper. To achieve remote control operation of the chassis, a hydraulic motor drive scheme is adopted. The adjustment range of the rubber roller was analyzed, and gear toothed belt type rubber roller spacing adjustment mechanism was designed. A picking head posture adjustment system was established,and the buffering effect of the gas spring in the picking head posture adjustment process was analyzed. Using the harvest rate of camellia fruit and flower bud damage rate as indicators, a four factor three-level orthogonal experiment was conducted with rubber roller spacing, layer depth, layer thickness, and rubber roller speed as factors. The weighted average method was used to calculate the weighted average scores of each picking parameter group, and the optimal parameter combination was obtained when the rubber roller spacing was 18 mm, the layer depth was 700 mm, the layer thickness was 260 mm, and the rubber roller speed was 50 r·min^-1. Under this work condition, the harvest rate of camellia fruit was 95.20%, and the flower bud damage rate was 6.90%. The results indicate that the remote-controlled layered harvester meets the technical requirements for camellia fruit harvesting and can provide reference for the development of mechanical harvesting machines for camellia fruit.

Matcha is a powdered green tea produced through shaded cultivation, steam fixation, and fine grinding. It has gained global popularity and has become an important tea product globally. This paper systematically reviews the development status of the global matcha industry with a focus on research advances in its quality and safety evaluation systems. In terms of quality assessment, the current quality grading standards based on sensory evaluation and instrumental analysis are elaborated, along with comprehensive evaluation methods for color, aroma, and taste. Regarding safety evaluation, the focus is placed on key risk factors such as heavy metals and pesticide residues, with both relevant limit standards and corresponding detection technologies summarized. Furthermore, the application potential of emerging rapid screening technologies, including near-infrared spectroscopy, hyperspectral imaging, electronic nose, electronic tongue, and biosensors, in the quality monitoring and safety evaluation of matcha is discussed. The purpose of this review is to provide systematic theoretical references and technical support for promoting the standardization, refinement, and high-quality development of the matcha industry.

Postharvest pears are prone to quality deterioration due to metabolic imbalances. Low-temperature storage is a crucial technique for delaying fruit senescence and maintaining quality. In recent years, metabolomics has been extensively used to reveal the metabolic changes in different pear varieties under low-temperature storage. However, inappropriate low temperatures or prolonged storage can induce cold stress. The molecular mechanisms involve the cascade regulation of cold-responsive genes by transcription factors in the low-temperature signal transduction pathway, subsequently triggering responses in phenylpropanoid metabolism and the reactive oxygen species scavenging system. These processes lead to membrane lipid peroxidation, energy metabolism imbalance, and abnormal accumulation of secondary metabolites, ultimately resulting in typical quality deterioration such as browning, lignification, and aroma loss. Therefore, low-temperature storage often requires combination with other preservation technologies to alleviate chilling injury. This article systematically elaborates on the physiological and metabolic dynamics of pear fruit under low-temperature storage and its molecular regulatory network, reviews the recent advances in the application of low-temperature synergistic technologies for chilling injury prevention and control, and prospects future research directions for analyzing quality changes and developing precise regulation technologies based on multi-omics technologies aiming to provide a theoretical basis for optimizing postharvest preservation technologies for pear fruits.